Method of injection into meat and pickle injector for use therein

ABSTRACT

Providing a method of injection into meat in which brine for curing or seasoning liquid is uniformly dispersed in a green meat efficiently and continuously without deteriorating a meat property; curing and seasoning can be accomplished without using a tumbling machine, a massage machine or the like for a long time; and the brine for curing and the seasoning liquid can be uniformly dispersed even if there is a difference of injection resistance in meat property. This can be achieved by using a pickle injector which is provided with a high-pressure liquid generator constituted of a plunger pump or the like, a coherent stream injection nozzle for injecting the brine for curing and a pressure control mechanism which can raise an injection pressure gradually from zero or a low pressure while injecting the liquid substance when the brine for curing is injected from the nozzle to the green meat.

This application is a divisional application filed under 37 C.F.R. 1.53(b) of application Ser. No. 09/076,729 filed May 13, 1998, now U.S. Pat.No. 6,014,926,

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

This application claims priority of Japanese Application Nos. 9-121924,filed May 13, 1997; No. 9-162964, filed Jun. 19, 1997; and No. 9-253678,filed Sep. 18, 1997, the disclosures of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to an injection method in which brine forcuring, seasoning liquid or another liquid substance is injected to ablock of pork, beef, poultry meat or another meat and the liquidsubstance is uniformly dispersed and a pickle injector for use in themethod. Also, the present invention relates to a method of manufacturingmeat products of pork, beef, poultry meat or the like, for example,cooked meat products or a raw ham or other uncooked meat products in ashort time by using the injection method.

(2) Description of the Related Art

In meat processing there is a need for uniform dispersion of curingagent or seasoning in meat. In recent years, it has been common to use amulti-needle pickle injector.

By a method in which the multi-needle pickle injector is used, products,in which additives including brine for curing or seasoning liquid aredispersed more uniformly than former days, can be manufactured. However,immediately after injection, the liquid accumulates in portions intowhich needles are stuck. Therefore, after a dynamic stimulus is givenwith a tumbling machine, a massage machine or the like, a green meatneeds to be cured until the brine for curing or the seasoning liquidpermeates through the green meat and is uniformly dispersed. Then, theprocess can advance to the next step. In the existing circumstances,there is a problem that several days are taken to salt loin ham orboneless ham, or to season roast pork.

Additionally, the injection pressure of brine for curing in themulti-needle pickle injector is limited to about 12 kg/cm² owing to itsstructure. Among substances included in the seasoning liquid, alow-molecular substance such as salt can easily move inside the greenmeat. However, high-molecular substances, or substances having a highreactivity with meat constituent substances cannot easily move insidethe green meat. As a result, the liquid is defectively dispersed.

For refinement in the existing multi-needle pickle injector, it isnecessary to further increase the needle density of the multi-needlepickle injector. However, even a fine needle has a diameter of about 3mm, and the width of a jig for fixing needles is also present.Therefore, it is difficult to improve upon the existing needle intervalof 12-25 mm. Also, even if the improvement can be accomplished, anincrease of the needle density is required, so that when the needles areput into and taken from the meat, resistance increases. Then, it becomespractically difficult to operate the device. Consequently, the injectionby means of the multi-needle pickle injector cannot achieve an object ofuniformly dispersing the liquid in the green meat in a short time.

Also, when the liquid is injected to a large green meat with theconventional multi-needle pickle injector, portions of a single greenmeat have different hardnesses. Even if uniform injection of the liquidis attempted, it cannot be uniformly injected because of a difference ofinjection resistance in meat property. For example, in Japanese UtilityModel Publication No. 11799/1985 and Japanese Patent ApplicationLaid-open No. 209693/1994, there are disclosed methods for solving theununiformity of the brine for curing injection due to a differencebetween injection resistances of the meat. By the methods, however, itis difficult to obtain highly precise results. The methods disclosed inthese reference are not satisfactory.

On the other hand, for the utilization of a needleless pickle injectorand its injection method to a ham and another processed meat, thefollowing prior art is known.

In Japanese Patent Application Laid-open No. 244906/1993, there isdisclosed a method in which a liquid substance such as brine isintroduced into a piece of meat with the needleless pickle injectorunder a high pressure by using spray nozzles. The pickle injector has astructure in which the thickness of a green meat is made constant by apressure roller and a conveyor and the liquid substance is injected fromthe underside by the spray nozzles. Further, it is described that theinterval between the nozzles is within 20 mm and the liquid substancecan be injected into a 20 mm thick meat. Since diffusing spray nozzlesare used in the pickle injector, as shown in FIG. 5 of the publication,the liquid substance spreads in a concentric manner. Non-injectedportions and liquid overlapped portions are generated. It cannot be saidthat the liquid substance can be uniformly injected and dispersed by themethod. Also, the pickle injector has a structure in which the meat iscrushed and thinned, and the injection is then performed. The meat isdamaged by a high spray pressure which concentrically spreads.Therefore, the pickle injector cannot be used for a thick meat.

Also in the method, the meat may be cracked and broken by the pressureroller.

Therefore, in the introduction method, even if thickness is reduced bythe pressure roller, it is difficult to apply the method to pork ham orloin with a thickness exceeding 30 mm.

It is disclosed in the specification of U.S. Pat. No. 2,418,914 that, inorder to soften meat in a short time after slaughtering, a meat softenerof a lipid substance and a small amount of water or other edibleparticles are sprayed over a meat surface under high pressure at highspeed and allowed to permeate through a depth of the meat and that meatmuscle fibers are mechanically ruptured. However, the dispersedcondition and the like of the edible particles are not detailed.

It is disclosed in the specifications of the U.S. Pat. Nos. 3,016,004and 3,436,230 that a tip end of a nozzle is brought in contact with ameat surface to inject preservative liquid or another liquid under ahigh pressure and disperse the liquid without rupturing meat fibers. Itis described as a concrete example that a high-speed liquid flow isinjected to lean and fat of bacon belly by using an automatic injectorwhich is provided with a lean injection nozzle and a fat injectionnozzle.

In the specifications of U.S. Pat. Nos. 3,769,037 and 3,649,299, thereis described a method for effectively limiting a penetration depth ofliquid of softener and/or flavor application agent into meat. Byallowing coherent stream from three directions to collide against oneanother at a focal point and losing and diffusing energy, thepenetration depth is limited.

In a device described in the specification of the U.S. Pat. No.3,675,567, while the injection nozzle described in the aforementionedspecifications of the U.S. Pat. Nos. 3,769,037 and 3,649,299 is moved atthe same speed as the meat, by the control of a solenoid valve which canbe quickly turned on/off by an electric timer, softener, flavorapplication agent or another liquid is injected to poultry meat under apressure of 1000 to 5000 psi and at a high speed.

The specifications of the U.S. Pat. Nos. 3,739,713 and 3,814,007disclose an injection device in which liquid pressure in a nozzle pathis increased until it reaches a predetermined value. After a valve isopened, liquid is quickly injected at a dash from tip ends of pluralnozzle paths having various lengths in accordance with an amorphousgreen meat. In the device no liquid leakage occurs.

It is described in the specification of the U.S. Pat. No. 5,053,237 thatto enhance softness and sensory quality of low-class meat, vegetableoil, fat or another binder is injected into a moving meat from a nozzledisposed at a predetermined distance from the meat under such a pressurethat the binder can sufficiently penetrate through meat tissue. Meatconnective tissue can be cut in transverse and vertical directions.

It is described in the specification of the U.S. Pat. No. 5,112,270that, in order to perform water-jet slaughtering, cranium is rupturedunder an ultra-high pressure (3000 to 4000 kg/cm²).

In the specification of U.S. Pat. No. 5,200,223, there is described amethod in which liquid is intermittently or periodically jetted in theform of a fine jet flow in a short time from high-pressure nozzle tomeat continuously conveyed in a piping and the liquid is injected to agiven depth of the meat.

In the specification of U.S. Pat. No. 5,176,071, there is described amethod and a device in which, in order to improve a means for causing nodamage on meat, a green meat on a conveyor is flattened to apredetermined thickness by a pressure roller and brought into contactwith a spray nozzle. Without spraying injection stream to an outersurface of the meat, seasoning liquid or the like is uniformlydispersed.

However, in some of the aforementioned needleless pickle injectors andthe injection methods using the injectors, the meat surface is damaged.In the other, the thickness of the green meat as an object is limited.They have no general-purpose properties. Above all, in a practical levelfor raw-material meat varying in thickness, it cannot be absolutely saidthat the liquid substance can be uniformly dispersed. Then, an injectionmethod in which the injection pressure is controlled while injecting theliquid substance in such a manner that the liquid substance can beuniformly dispersed and a pickle injector for use in the method have notbeen known.

On the other hand, a meat product is largely classified into a cookedmeat product subjected to heating and sterilizing and a uncooked meatproduct not subjected to heating and sterilizing. A raw ham belongs tothe uncooked meat product. By using salt or the like, its keepingquality is enhanced. As a curing method for manufacturing the raw ham, adry curing method, a brine curing method and a single needle injectionmethod are authorized according to the Japanese food hygiene law.Generally, in the dry curing method, after shaping raw-material meat,the meat is directly rubbed with salt or the like. After the meat iscured in a refrigerator for 2 to 3 weeks, decuring is performed asrequired. Thereafter, smoking/drying is performed for 3 to 7 days. Inthe brine curing method, after shaping raw-material meat, the meat ispickled in curing liquid of salt or the like dissolved in water forabout 2 weeks. Decuring is performed as required. Thereafter,smoking/drying is performed for 3 to 7 days. In the single needleinjection method of curing liquid, after shaping raw-material meat,curing liquid which is formed by dissolving salt or the like in water isinjected with a needle. After the meat is cured in a refrigerator for 7to 10 days, smoking/drying is performed for 3 to 7 days.

Among the aforementioned curing methods, in the dry curing method, thecuring period is as long as 2 to 3 weeks as aforementioned. Much spacein the refrigerator is necessary. The salt content of the product tendsto be high. Additionally, there is a large difference of salt content ineach product. In the brine curing method, the curing period is slightlyshortened as compared with the dry curing method, but as long as about 2weeks. Each product has a large difference of salt content in the samemanner as in the dry curing method. According to the single needleinjection method, it takes about 2 weeks to manufacture the raw ham. Themethod is superior in manufacture period to the dry and brine curingmethods in which the manufacture period is three to four weeks. However,a predetermined quantity of the curing liquid needs to be manuallyinjected uniformly to the green meat with one needle. Therefore, themethod provides a bad productivity and requires skill in operation. Itcannot be absolutely said that the method is efficient.

Also, for the raw ham, in a known method, to shorten the curing period,a pork block and Brine are thrown into a massage machine and massagingis performed to allow the Brine component to permeate the pork block.Thereafter, manufacture is performed in a conventional method. Thereby,manufactured is a raw ham which has a small salt-content gradient in itssurface and central portion, a low salt-content concentration andsoftness (Japanese Patent Application Laid-open No. 149/1995). To obtaina raw ham with a little dispersion of salt concentration in a product,in a known method, raw-material pork salted in a high salt concentrationis desalted by circulating brine with a salt concentration of 1 to 4%(Japanese Patent Application Laid-open No. 141763/1994). Also, tomanufacture a raw ham, a raw bacon or another uncooked meat product in ashort period, a block of livestock meat is cured by using a curing agentand 5 to 30 parts by weight of sugar relative to 100 parts by weight ofthe livestock green meat. Drying and smoking are performed inconventional methods. Such method of manufacturing a uncooked meatproduct is also known (Japanese Patent Application Laid-open No.284877/1994).

SUMMARY OF THE INVENTION

An object of the invention is to solve the problems in theaforementioned conventional multi-needle and needleless pickleinjectors. Not only for thin but also thick raw-material meats andfurther in raw-material meats different in configuration and size,without deteriorating meat property, brine for curing or seasoningliquid is efficiently and continuously dispersed uniformly in a greenmeat. Without operating a tumbling machine, a massage machine or thelike for a long time, curing or seasoning can be accomplished. Further,even when there is a difference of injection resistance in meatproperty, the brine for curing or the seasoning liquid can be uniformlydispersed. An object of the invention is to provide such a practicalinjection method, a pickle injector for use in the method and a methodof manufacturing a meat product, especially a raw ham or anotheruncooked meat product by using the injector.

To find out an injection method in which the brine for curing or theseasoning liquid can be uniformly dispersed, inventors et al. firststudied the multi-needle pickle injector mainly used at present, but nosolution was found. Therefore, for the injection method using theneedleless pickle injector, a prototype machine provided with ahigh-pressure liquid generator and a straight water flow injectionnozzle (coherent stream injection nozzle) was produced, and studies werestarted. However, even by using the conventional needleless pickleinjector, expected results could not be obtained. Then, to find outconditions actually applicable to meat processing, the prototype machinewas modified. Additionally, a basic research of properties in theinjecting and dispersing of the liquid substance into the green meat waspursued.

(Injection Depth)

As the property of the injecting and dispersing of the liquid substanceinto the green meat, first an injection depth of the liquid substanceinto the green meat (a distance from a green meat surface to a portionin the green meat which the injected liquid substance reaches at thetime of injection) was studied by using pork ham. As a result of anexperiment repeated by varying injection pressure and time, it was foundthat the injection depth is not usually related with the injection time,but is correlated with the injection pressure. Then, while conditionssuch as a nozzle-hole size which influence the pressure are constantlymaintained, the experiment was repeated again. As a result, it was foundthat the injection depth and the injection pressure have a relationshipshown in FIG. 1.

As clearly seen from FIG. 1, when the nozzle-hole size or otherconditions influencing the pressure are made constant, the relationshipbetween the injection depth of the liquid substance into the green meatand the maximum value of the injection pressure (hereinafter referred toas "the maximum injection pressure") can be represented by a linearexpression. It was found that when the maximum injection pressure is thesame, the injection depth is the same.

For example, when the nozzle-hole size is made constant as 3/1000 inch,the relationship between the injection depth and the maximum injectionpressure can be represented by the following linear expression:

P=30.0H

P; maximum injection pressure (kg/cm²)

H; injection depth (mm)

The experiment showed that the injection depth of the liquid substanceinto the green meat can be controlled by the maximum injection pressure.As a result, by measuring the thickness of the green meat beforehand,the necessary maximum injection pressure can be calculated. It has beenfound that the injected liquid substance can be prevented from passingthrough the green meat and jetting out of the green meat. Conversely,the liquid substance can be prevented from failing to be sufficientlyinjected to the end.

(Injection Quantity)

As the property of the injecting and dispersing of the liquid substanceinto the green meat, next an injection quantity of the liquid substanceinto the green meat was studied by using pork ham. The inventors et al.used a pickle injector having an modified straight water flow injectionnozzle (coherent stream injection nozzle) to repeat an experiment byvarying the injection pressure and time. It was found that when apressure rising quantity per unit time (hereinafter referred to as "thepressure rising rate") is constant, the injection quantity is notrelated with the injection pressure, but is correlated with theinjection time. Then, the experiment was again repeated to clarify therelationship between the injection quantity and the injection time. As aresult, it was found that the injection quantity and the injection timehave a relationship shown in FIG. 2.

As clearly seen from FIG. 2, the relationship between the injectionquantity of the liquid substance into the green meat and a period oftime for reaching the maximum injection pressure (hereinafter referredto as "the injection reaching time") can be represented by a linearexpression.

The injection quantity can vary with the number of nozzles, thenozzle-hole size, a flow rate of a pump and the like. For example, whenthe nozzle-hole size is set to 3/1000 inch and the other conditions aremade constant, the relationship between the injection quantity and theinjection reaching time can be represented by the following linearexpression:

T=Q/45

T; injection time (seconds)

Q; injection quantity (g)

From the experiment, it was found that when the injection reaching timeis the same, the injection quantity is the same. Also, it was recognizedthat the injection quantity of the liquid substance into the green meatcan be controlled by the injection reaching time.

(Injection Ratio)

Subsequently, as the property of the injecting and dispersing of theliquid substance into the green meat, an injection ratio of the liquidsubstance into the green meat was studied. Here, the injection ratio isrepresented by the following expression:

    Injection ratio (%)=(green meat weight+injection liquid weight)/green meat weight×100

In a repeated experiment, by using the pickle injector having thecoherent stream injection nozzle and varying the injection pressure andtime, the liquid was injected to a block of pork loin from nozzlesarranged at constant intervals at an equal density, and the injectionratio was measured. As a result, it was found that in the case of thesame injection ratio, the injection ratio is correlated with the maximuminjection pressure and the injection reaching time. Then, by regulatingthe thickness of the green meat to vary the maximum injection pressureand by regulating the injection reaching time based on the resultsobtained beforehand by the injection into the green meat to obtain theinjection ratios of 110, 120, 130 and 140%, the relationship of themaximum injection pressure and the injection time was examined wheninjection was performed into 20 green meat for each case. As a result,it was found that the maximum injection pressure and the injection timehave a relationship shown in FIG. 3.

As seen from FIG. 3, in each injection ratio, points indicative of therelationship of the maximum injection pressure and the injectionreaching time are distributed on a straight line. This means that whenthe pressure rising rate derived from the relationship of the maximuminjection pressure and the injection reaching time is the same, bychanging the maximum injection pressure in accordance with the thicknessof the green meat, the injection time also changes. As a result, theequal injection ratio can be obtained.

Also, the experiment showed that when the pressure rising rate(represented by a straight slope in FIG. 3) is changed, the injectionratio changes. As a result, it was found that by adjusting the pressurerising rate, the injection ratio can be controlled.

The present inventors modified the prototype machine based on theaforementioned findings obtained from the basic research of theproperties in the injecting and dispersing of the liquid substance intothe green meat in the case of using the high-pressure liquid generatorand the coherent stream injection nozzle, especially, based on thefinding that the injection ratio can be controlled by adjusting thepressure rising rate. It was found that the liquid substance can beuniformly dispersed by controlling the injection pressure whileinjecting the liquid substance. Then, the present invention has beencompleted.

The invention provides a method of injecting a liquid substance into agreen meat in which when the liquid substance is injected to the greenmeat by using a coherent stream injection nozzle, and the injectionpressure is controlled while injecting the liquid substance.

The invention provides a method of injecting a liquid substance into agreen meat in which a straight water flow (coherent stream) injectionpressure is regulated beforehand to a pressure suitable for physicalproperties and thickness of the green meat or physical properties of theliquid substance as required. A coherent stream injection nozzle isbrought in contact with the preferably fixed green meat. While injectingthe liquid substance by using the coherent stream injection nozzle, theinjection pressure is controlled to gradually increase or change from 0or a low pressure.

The invention provides method of injecting a liquid substance into agreen meat in which when the liquid substance is injected to the greenmeat by using a coherent stream injection nozzle, by changing a risingrate of the injection pressure in the range of, for example, from 100 to20000 kg/cm² ·second, whereby an injection ratio of the liquid substanceinto the green meat is controlled.

The invention provides a method of manufacturing a meat product,especially, a raw ham or another uncooked meat product in which theaforementioned injection method is used.

The invention provides a pickle injector being a device for injecting aliquid substance into a green meat provided with a high-pressure liquidgenerator, a liquid-substance injecting section and a pressurecontroller which can control an injection pressure while injecting theliquid substance when the liquid substance is injected from theinjecting section to the green meat. Also, the invention provides apickle injector which is further provided with a meat thicknessregulating section for making constant the meat thickness of a greenmeat and a meat thickness measurement section.

The invention provides a pickle injector in which the pressurecontroller in the aforementioned pickle injector has a pressure controlmechanism which can gradually raise the injection pressure from 0 or alow pressure; a pickle injector which controls the injection pressure bycontrolling the number of rotations of a servo motor or the like; and apickle injector having a residual pressure cut means which can quicklyreset to 0 or a low pressure an injection pressure gradually raised from0 or the low pressure.

The invention provides a pickle injector in which the injecting sectionin the aforementioned pickle injector has a coherent stream injectionnozzle; a pickle injector in which the injecting section has onemanifold or plural interconnected manifolds for branching a singlestream to plural streams; and a pickle injector in which one end of arobot hand is provided with the injecting section and a green meatconveying means.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing a relationship of an injection depth and amaximum injection pressure in the case of injection with a pickleinjector of the invention.

FIG. 2 is a graph showing an injection time and an injection quantity inthe case of injection with the pickle injector of the invention.

FIG. 3 is a graph showing a relationship of the maximum injectionpressure and the injection time at injection ratios of 110, 120, 130 and140% in the case of injection with the pickle injector of the invention.

FIG. 4 is a graph showing a change with time in injection pressure inthe case of injection with a conventional needleless pickle injector.

FIG. 5 is a graph showing a change with time in injection pressure inthe case of injection with a needleless pickle injector of theinvention.

FIG. 6 is a perspective view of a pickle injector of the invention.

FIG. 7 is a front view of a robot in the pickle injector of theinvention.

FIG. 8 is a perspective view of another pickle injector of theinvention.

FIG. 9 is a vertical sectional view of an injecting section in thepickle injector of the invention.

FIG. 10 is a bottom view of the injecting section of the pickle injectorof the invention.

FIG. 11 is an explanatory view showing a comparison of a distributedcondition of salt after injection between the pickle injector of theinvention and a conventional multi-needle pickle injector.

FIG. 12 is an explanatory view showing a comparison of a distributedcondition of colorant after injection between the pickle injector of theinvention and the conventional multi-needle pickle injector.

FIG. 13 is an explanatory view showing transition of the raw hammanufacture period and the central-portion water activity value.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the invention, examples of meat include, for example, pork, beef,poultry meat, horse meat, mutton, internal-organ meat, meat with bonesand meat with skin, fish meat and the like. Any type of meat for foodcan be used.

In the invention, example of a liquid substance include, for example,brine for curing, seasoning liquid, modifier of lipid or another tissue,natural keeping agent, natural colorant, enzyme, solution ofmicroorganism or the like and dispersion suspension. Liquid substanceincluding gas or any other liquid substance can be used as long as itcan be injected from a coherent stream injection nozzle or anotherinjecting section into a green meat.

In the invention, a meat product means any processed meat. For example,according to the classification in the food hygiene law, the meatproduct corresponds to a dry meat product, an uncooked meat product, aspecific cooked meat product or a cooked meat product. Among these, theuncooked meat product means a meat product which is not subjected to aprocess of heating a green meat to its center, for example, at 60° C.for 30 minutes, a process which provides an effect equal to or exceedingan effect of the heating process or another heating/sterilization. Forexample, a raw ham or a raw bacon of various raw materials can beexemplified.

In the invention, a straight water flow (coherent stream) means a flowof liquid substance which does not spout in a concentrically diffusedmanner, but spouts in a converged straight manner. A coherent streaminjection nozzle means a nozzle for spouting the coherent stream. Alsoin the invention, an injection pressure means a liquid pressure of theliquid substance immediately after the liquid substance is spouted fromthe coherent stream injection nozzle. It is usually measured as a liquidpressure in a piping between a high-pressure liquid generator and thecoherent stream injection nozzle by, for example, a pressure sensor. Byproviding the pressure sensor, the injection pressure can be furtherregulated to a set value.

In the invention, "controlling the injection pressure while injectingthe liquid substance" means that the injection pressure is controlled bya means for controlling the injection pressure from the start ofinjection of the liquid substance untill the completion thereof, andexcludes the case where the liquid substance is injected at a dash byopening/closing a valve disposed in a high-pressure piping and the casewhere the injection pressure is changed beforehand by replacing a nozzledifferent in hole diameter prior to injection. Then, in the invention inwhich the injection pressure is controlled while the liquid substance isbeing injected, the rising rate of the injection pressure is usually setin the range of 100 to 20000 kg/cm² ·second. By comparing a change ofpressure in the conventional injection method utilizing theopening/closing of the valve shown in FIG. 4 with that of pressure inthe injection method of the invention shown in FIG. 5, the technicalmeaning of "controlling the injection pressure while injecting theliquid substance" is further clarified.

In the invention, in order to uniformly disperse the liquid substance inthe green meat, it is preferable that while injecting the liquidsubstance from the coherent stream injection nozzle, the injectionpressure is gradually, preferably gradually and continuously raised from0 or a low pressure. When the coherent stream injection nozzle is used,as the property in the injecting and dispersing of the liquid substanceto the green meat, the injected liquid substance is dispersed in atransverse direction at a predetermined depth by the resistance of meattissue. When the injection pressure is gradually raised, the injectiondepth changes in accordance with the injection pressure. The liquidsubstance is dispersed in the transverse direction by the resistance ofthe meat tissue at the depth. Such phenomenon repeatedly occurs with theincrease of the injection depth. Then, the liquid substance is uniformlydispersed from surface to bottom of the green meat. Therefore, bygradually raising the injection pressure from 0 or a low pressure, aproduct superior in uniform dispersion of the injected liquid substancecan be obtained. Additionally, for the purpose of dispersing the liquidsubstance in a specific portion of the green meat and another purpose,the injection pressure can be stepwise raised from 0 or a low pressurewithout being raised gradually and continuously.

When, instead of controlling the injection pressure while injecting theliquid substance, the injection pressure is rapidly increased from thestart as in a conventional case, then straightness is strengthened andthe liquid substance is not dispersed in the vicinity of the nozzle.Then, the liquid substance is accumulated in portions at the injectiondepth matched with the injection pressure. To obtain a uniformdispersion state in the green meat, by using the pickle injector of theinvention, while injection is being performed, the injection pressureneeds to be gradually raised from 0 or a low pressure to the maximuminjection pressure at a constant pressure rising rate.

The pickle injector of the invention is a device for injecting theliquid substance into the green meat. The pickle injector is providedwith a high-pressure liquid generator, a liquid-substance injectingsection, and a pressure controller which can control the injectionpressure while injecting the liquid substance when the liquid substanceis injected from the injecting section to the green meat.

The high-pressure liquid generator in the pickle injector of theinvention may be any mechanism, as long as it can increase the pressureof the liquid substance to a high level, for example, 7 to 3000 kg/cm².Examples of the high-pressure liquid generator include reciprocal pumpssuch as a plunger pump and a fluid pressure cylinder as well as pumpssuch as a rotation pump and a centrifugal pump. Members other than thepumps may be used, if the pressure of the liquid substance can be sethigh. By controlling the number of rotations of a motor, the plungerpump or another pump is operated and output of the pump is controlled.In this or another case, the high-pressure liquid generator can beconstituted integrally with the pressure controller described later. Inthe case of controlling the pressure with a valve or the like disposedin a high-pressure piping or in another case, the high-pressure liquidgenerator and the pressure controller may be provided separately.

The injecting section in the pickle injector of the invention may be ofany type if it has an exhaust port from which the high-pressure liquidsubstance can be injected into the green meat. For a tip-endconfiguration, a nozzle is preferable. More preferable is a coherentstream injection nozzle which, instead of concentrically diffusing andspouting the liquid substance, can inject a flow of the liquid substancespouted in a straight converged manner, that is, a coherent stream.Additionally, in a particular process, a spray injection nozzle or aneedle nozzle may be used.

Also, the high-pressure liquid substance is transferred from thehigh-pressure liquid generator via the high-pressure piping to theinjecting section, and it is preferable to use the injecting sectionwhich has a member called a manifold for branching a single flow fromthe high-pressure piping to plural flows. The manifold is preferablyplaced on the tip end of the injecting section, but can be placed midwayin the piping as the case may be.

The injecting section of the conventional high-pressure liquid generatoris of a single-hole type or has a form in which the piping in themanifold is branched radially. The present inventors have manufactured amanifold especially suitable for a pickle injector for meat, and apiping in the manifold is branched and the branched pipes are parallellyarranged. Here, the parallel arrangement includes not only thearrangement where the pipes are arranged parallel in a row but also thearrangement where the pipes are arranged zigzag or parallel in multiplerows. By arranging nozzles parallel, a nozzle interval can be narrowedto 10 mm or less, e.g., 5.6 mm for injection. Therefore, a highly denseand uniform injection is feasible. Further preferably used is a manifoldwhich has multiple coherent stream injection nozzles arranged parallelin this manner.

When the manifold is used, the high-pressure liquid substance isinjected as the coherent stream from the nozzle on the tip end of eachpiping. The liquid substance is injected simultaneously from theparallel arranged nozzles to the green meat. Also, when one manifold isprovided with multiple nozzles, the liquid substance can be efficientlyinjected in one injection process. However, if one manifold is providedwith an excessively large number of nozzles, load is applied to thehigh-pressure liquid generator. In this case, plural manifolds arepreferably interconnected, a valve is placed on the upstream side ofeach manifold and the valves are sequentially opened/closed in such amanner that the manifolds sequentially spout the liquid substance. Forexample, when three interconnected manifolds are operated by switchingvalves or the like, the raising/lowering of the liquid substancepressure can be saved twice as compared with the case where injection isperformed three times with one manifold. High-speed operation can beadvantageously accomplished.

The pressure controller in the pickle injector of the invention may beof any type if it has a mechanism for controlling the injectionpressure. The pressure controller can be largely classified into acontroller having a means for controlling the pressure in thehigh-pressure liquid generator, a controller having a means forcontrolling the pressure in the high-pressure piping or the injectingsection and a controller having a combination of these means.

In the controller having the means for controlling the pressure in thehigh-pressure liquid generator, for example, a plunger of a plunger pumpis operated by using a servo motor, a stepping motor or a three-phasemotor having an inverter and controlling the number of rotations or themotor to control an output of the high-pressure liquid generator, i.e.,the injection pressure. Alternatively, a piston of an oil pressurecylinder, a water pressure cylinder, an air cylinder or the like isoperated by using a variable adjustment valve or the like andcontrolling a fluid pressure to control the output of the high-pressureliquid generator, i.e., the injection pressure.

Examples of the controller having the means for controlling the pressurein the high-pressure piping include a controller in which the output ofthe high-pressure liquid generator is made constant and one or morepressure regulation valves are disposed in the high-pressure piping, acontroller which can operate the pressure regulation valve in thehigh-pressure piping by using an actuator, and a controller in which abuffer such as a piston cylinder for absorbing the pressure is placed onan end of a branch pipe connected to the high-pressure piping. Also, asthe controller having the means for controlling the pressure of theinjecting section available is a controller in which the output of thehigh-pressure liquid generator is made constant and a nozzle-holediameter and the number of nozzles interconnected to the injectingsection are changed.

Also, if necessary, control can be performed by combining the means forcontrolling the pressure in the high-pressure liquid generator and themeans for controlling the pressure in the high-pressure piping and theinjecting section. In any case, control can be performed simply andexactly and various pressure controls can be performed. Therefore,preferable is a system in which by using the servo motor or the like,the number of rotations of the motor is controlled.

For example, the case where a servo motor constituted of a motor, adriver and a programmable controller (PLC) is used will be described.The driver is connected to the PLC. In response to an output indicativeof a motor operating condition transmitted to the PLC and an instructionof PLC, the motor is operated. The motor rotates in proportion to thenumber of pulses received by the driver from the PLC. The rotation speedis changed in accordance with the rate (time density) of the pulse.Then, when a high-pressure pump is operated by the servo motor, theliquid flow rate is generally proportional to the number of rotations ofthe motor (positioning). The liquid pressure is proportional to thenumber of rotations of the motor.

The injection of the liquid substance into the green meat by means ofthe pickle injector of the invention is continuously repeated. When moregreen meats are processed, the injection frequency of the liquidsubstance per unit time needs to be increased. In this case, before theinjection pressure is gradually raised from 0 or a low pressure is resetto 0 or the low pressure, the next injecting operation is started. As aresult, the injection pressure cannot be raised gradually from 0 or thelow pressure. In this case, by providing the pressure controller withthe residual cut means, the injection pressure which has been graduallyraised from 0 or the low pressure can be quickly reset to 0 or the lowpressure. An example of the residual pressure cut means is a reliefvalve placed on a part of the high-pressure piping. By quickly openingthe relief valve after completing the injection, the pressure of theliquid substance after the injection can be quickly reset to 0 or thelow pressure. An example of another residual cut means is a means inwhich a buffer such as the piston cylinder for absorbing the pressure isplaced on an end of a branch pipe connected to the high-pressure piping.In this case, after the injection is completed, the piston is retreated.The pressure of the liquid substance in the piping is absorbed. Then,the pressure of the liquid substance after the injection can be quicklyreset to 0 or the low pressure.

As aforementioned, to obtain the uniformly dispersed condition in thegreen meat, by using the pickle injector of the invention, whileinjection is being performed, the injection pressure needs to begradually raised from 0 or the low pressure to the maximum injectionpressure at a constant pressure rising rate. The necessary maximuminjection pressure can be regulated variously in accordance withphysical properties of the green meat (proportion of lean and fat, meathardness, the presence of bones and the like), thickness andconfiguration of the green meat, physical properties of the liquidsubstance (molecular weight of solute or dispersoid, viscosity,reactivity with meat components and the like), a distance between a tipend of the coherent stream injection nozzle and the green meat and thelike. The maximum injection pressure is usually set In the range of 7 to3000 kg/cm², preferably 300 to 2000 kg/cm².

If the maximum injection pressure is less than 7 kg/cm², the injectionpressure is lower than a stress of the green meat. Therefore, the liquidsubstance is not sufficiently dispersed in the green meat. Conversely,if the maximum injection pressure exceeds 3000 kg/cm², the green meat isdisadvantageously damaged.

Therefore, when the thickness of the usually used meat, the dispersionin the green meat, damages and the like are considered, the maximuminjection pressure is preferably set variously in the range of 300 to2000 kg/cm². The high-pressure liquid generator in the pickle injectorof the invention preferably has an ability to apply various pressures inthe range up to 3000 kg/cm².

For example, the physical properties of the green meat is largelyrelated with the injection resistance to the meat. The stress variesfrom about 7 kg/cm² to 26 kg/cm² with derivation or portion of the meat.The injection pressure of the conventional multi-needle pickle injectoris about 12 kg/cm² at maximum, which causes ununiformity in injectionbecause of a difference in derivation and portion of the meat. However,in the uniformly dispersed injection method of the liquid substance intothe green meat according to the invention, a remarkably high injectionpressure (coherent stream injection pressure) is used. Therefore, theproblem of non-uniform dispersion in an injection direction and adirection crossed at right angles to the injection direction due to adifference between injection resistances of the meat is solved. Also, bypressing the green meat by the manifold of the injecting section of thepickle injector with a constant force, the precision of uniformdispersion is further raised.

To prevent the liquid substance from passing through the green meat andspouting out of the green meat or conversely to prevent the liquidsubstance from being insufficiently injected and dispersed to the end,there is a technique in which a meat thickness is beforehand madeconstant by using a press roller or the like. As aforementioned, bycontrolling/adjusting the maximum injection pressure of the liquidsubstance from the coherent stream injection nozzle, the injection depthof the liquid substance can be controlled. Therefore, by providing thepickle injector of the invention with a meat thickness measurementsection, the maximum injection pressure is calculated based on ameasured value. All processes for controlling the pressure can becompletely automated. The meat thickness measurement section preferablyhas a mechanism for automatically measuring the meat thickness. Forexample, as the automatic meat-thickness measurement mechanism formeasuring a distance between upper and lower surfaces of the green meat,there is a system in which a nozzle disposed on a tip end of a robothand is brought into contact with the green meat to automaticallymeasure the meat thickness on the basis of a displacement of apotentiometer, and a system for automatically measuring the meatthickness by using a photo sensor. Furthermore, a system forautomatically calculating the meat thickness by image processing canalso be employed. Additionally, the automatic meat-thickness measurementmay be performed before the liquid substance is injected to the greenmeat. It can be performed simultaneously with the injection in the samemanner as the case where measurement is performed by using the nozzle onthe tip end of the robot hand.

Also, in the cases of a green meat having a constant thickness, a greenmeat having constant physical properties and the like, the maximuminjection pressure can be preset. Especially, in the case of green meatssuch as outside and boston butt in which a hard film-like layerconstituted of a connective tissue exists, and in the case of a greenmeat such as belly in which lean and fat are alternately laminated and ahard film-like layer constituted of a connective tissue exists, themaximum injection pressure may be preset in such a manner that theliquid substance can pass through the green meat and spout out of thegreen meat. For example, for the belly as a raw material of bacon, inthe conventional multi-needle pickle injector, the liquid substance isinhibited by the hard film-like layer constituted of the connectivetissue from penetrating further. Additionally, since the liquidsubstance is accumulated in fat layers in which the liquid substancedoes not have to be dispersed, the soft fat layers disadvantageouslyswell. However, according to the invention, the liquid substance ishardly dispersed in the fat layers with a small stress, but uniformlydispersed entirely in lean layers including the hard film-like layer andfarther layers. A superior bacon can thus be obtained.

In the invention, as aforementioned, by controlling/adjusting theinjection time elapsed until the maximum injection pressure of theliquid substance from the coherent stream injection nozzle is reached,the injection quantity of the liquid substance can be controlled. Theinjection time elapsed until the maximum injection pressure is reachedcan be set variously in accordance with the property of meat, physicalproperties of the liquid substance or the like. The injection time isusually set to 0.05 to 10 seconds, preferably 0.1 to 5 seconds, morepreferably 0.3 to 2 seconds.

If the injection time is less than 0.05 second, a necessary pressure isnot reached or a small flow rate may result in insufficient dispersionin the green meat. Also, if it exceeds 10 seconds, injection takes time,the injection quantity increases, but a retention force of the liquidsubstance in the green meat has a limitation. Therefore, at the time ofinjection, the quantity of liquid substance leaking from injectedportions increases. The precision of injection ratio tends to beworsened.

In respect of a high precision of the set injection ratio and theinjection efficiency, the injection time is preferably set to 0.3 to 2seconds.

In the invention, as aforementioned, by changing the pressure risingrate of the liquid substance from the coherent stream injection nozzle,the injection ratio of the liquid substance into the green meat can becontrolled/adjusted. In the conventional method in which the liquidsubstance is injected, for example, only by opening/closing one valveinstead of controlling the injection pressure during injection as in theinvention, the pressure momentarily rises. Thereafter, the pressurechanges as shown in the aforementioned FIG. 4. In the conventionalmethod, the injected liquid substance cannot be uniformly dispersed inthe green meat. However, in the invention, by setting the pressurerising rate to 100 to 20000 kg/cm² ·second, preferably 200 to 10000kg/cm² ·second, more preferably 1000 to 4000 kg/cm² ·second, control isperformed while injection is being performed, so that the liquidsubstance can be uniformly dispersed in the green meat.

When the pressure rising rate is less than 100 kg/cm² ·second, injectiontakes time, the injection quantity increases, but the retention force ofthe liquid substance in the green meat has a limitation. Therefore, thequantity of return pickle increases, and the precision of injectionratio tends to be worsened.

Also, when the pressure rising rate exceeds 20000 kg/cm² ·second, thepressure rising rate is so fast that the pressure rises at a dash likein the needleless injection of conventional patents in which the valveis opened/closed. It is difficult to control the injection pressurewhile injection is being performed. Therefore, sufficient dispersion inthe green meat cannot be achieved.

Further, to achieve a higher precision of the preset injection ratio andsufficiently uniform dispersion of the liquid substance in the greenmeat, the pressure rising rate is preferably set to 1000 to 4000 kg/cm²·second.

As aforementioned, the injection depth is proportional to the maximuminjection pressure, and the injection quantity is proportional to theinjection reaching time. For example, in the case of injection performedat the constant nozzle interval and at the equal density, when thepressure rising rate is the same, the thicker the green meat is, thehigher the maximum injection pressure becomes. In proportion to this,the injection time is lengthened, and the injection quantity isincreased. Conversely, when the green meat is thin, the maximuminjection pressure is lowered, and in proportion to this, the injectiontime is shortened. Therefore, the injection quantity is decreased.

For example, in the case that after the liquid substance is injected toa 10 cm square green meat, it is injected to a green meat reduced by 5cm of half only in height at the same pressure rising rate, thenecessary maximum injection pressure becomes half from a relationshipbetween the maximum injection pressure and the injection depth. Sincethe pressure rising rate is the same, the injection time also becomeshalf. As a result, since the green meat reduced half only in height hasa half injection weight, the same injection ratio is obtained.

Therefore, if the injection is performed at the same pressure risingrate at the constant nozzle interval at the equal density, the injectionquantity per unit volume is always equal, even in the case that thewidth, thickness or size of the green meat differs, whereby the sameinjection ratio can be obtained.

Also, in the case that the liquid substance is injected to the greenmeat having the same thickness at the constant nozzle interval at theequal density, the injection time is shortened and the injectionquantity is reduced, when the pressure rising rate is increased. As aresult, the injection ratio is lowered. Conversely, when the pressurerising rate is lowered, the injection time is lengthened and theinjection quantity is increased. As a result, the injection ratioincreases.

Therefore, by changing the pressure rising rate, the injection quantityper unit time changes. Consequently, by adjusting the pressure risingrate, the injection ratio can be controlled.

These controls are performed by the pressure adjustment means. Needlessto say, the pressure can be adjusted not only manually but alsoautomatically by a computer and an actuator based on the information ofmeat thickness and injection ratio.

In the invention, even substances which can scarcely be dispersed in thegreen meat can be uniformly injected and dispersed. Examples of thesubstances which can scarcely be dispersed in the green meat includeenzyme, microorganisms (lactic bacteria, yeast and the like),high-molecular substances, and substances with a high reactivity withmeat constituent substances. The substances cannot easily move insidethe green meat after injection or cannot be easily dispersed even bydynamic stimulus, standing period or another means. However, in theuniformly dispersed injection method of the invention, the maximuminjection pressure is remarkably high as compared with theaforementioned multi-needle injection method. Also, by controlling thepressure rising rate, even the hardly dispersed substances can beuniformly dispersed in the green meat.

In the pickle injector for use in the invention, by narrowing the nozzleinterval to 10mm or less, e.g., 5.6 mm, injection can be performed.Therefore, highly-dense and uniform injection is feasible. Since theinjection depth can be controlled by adjusting the maximum injectionpressure, the liquid substance is uniformly dispersed in the green meatat the time of injection. Thus, even the substances which can scarcelybe dispersed in the green meat are uniformly dispersed in the entiregreen meat simultaneously with injection.

In the invention, when the liquid substance is injected and dispersedinto the green meat by using the pickle injector, the tip end of thecoherent stream injection nozzle is brought into contact with the greenmeat. By spouting straight the liquid substance, the liquid substance ispreferably injected and dispersed into the green meat. In the case thatthe pickle injector is used for the curing and seasoning of the meat, ifa clearance is made between the coherent stream injection nozzle and thegreen meat as an object of injection, straightness is excessivelystrong, so that the dispersion is poor. However, the larger theclearance is, the higher the mix proportion of air becomes. When theinvention is applied to a hard lean meat, a meat product with adifferent texture can be obtained on occasion.

The pickle injector of the invention has a mechanism for determining aninjection position when the liquid substance is injected to the greenmeat, i.e., an injection positioning mechanism. The injectionpositioning mechanism is roughly divided into a mechanism in which theinjecting section is fixed in at least a conveying direction of thegreen meat and a mechanism in which the injecting section is moved in atleast the conveying direction of the green meat.

When the injecting section is fixed in at least the conveying directionof the green meat, as the injection positioning mechanism, there can beexemplified a conveyor for intermittently conveying the green meat to apredetermined position having the injecting section in the same manneras in the conventional multi-needle injector. When the green meat isstationary, the liquid substance is injected. Then, if the meatthickness is constant, the fixed injecting section does not have to bevertically moved. Usually, when the green meat is conveyed to thepredetermined position and stands still, the fixed injecting section islowered to inject the liquid substance from a top surface of the greenmeat or elevated to inject the liquid substance from an under surface ofthe green meat.

On the other hand, when the injecting section is moved, as the injectionpositioning mechanism, a robot hand having an injecting section on itstip end can be exemplified. The tip end having the injecting section ofthe robot hand is controlled by a controller or the like in compliancewith the green meat continuously or intermittently conveyed. Further,the robot hand can preferably move along X, Y and Z axes (the robot handcan move freely vertically, horizontally and back to forth). When theliquid substance is injected to the green meat by using the pickleinjector having the robot hand, injection can be performed from onedirection or two or more directions. The injection direction is notlimited to a vertical direction. By sequentially moving/rotating thenozzle position or a green meat mount, injection can be performed fromone direction or two or more directions, e.g., from the side, from belowor the like.

Also, a robot hand can be used which can not only move along the X, Yand Z axes but also direct its tip end to all azimuths in such a mannerthat injection can be performed from any face of the green me it. Whenthe pickle injector having the robot hand is used, the configuration ofthe green meat is automatically measured by a photo sensor or the like.In accordance with the measured configuration of the meat, injection canbe performed simultaneously or sequentially from two or more directionswithout sequentially moving/rotating the green meat mount.

Then, when the tip end of the injection robot hand is provided with agreen meat conveying means, by moving the green meat with the robothand, the liquid substance is injected. Simultaneously with completionof the injection, the treated green meat can also be conveyed to thenext process step. When the liquid substance is injected by moving thegreen meat with the green meat conveying means on the tip end of therobot hand, the green meat is fixed from opposite sides with a meatfixing slide guide before injection. This is preferable because nodamage is given to the meat. However, when muscle fibers or anothertissue of the meat is cut, a coherent stream may be injected bycontinuously moving the green meat. As the green meat conveying meansavailable is a means having a conveying claw or a conveying suctionportion. For secure conveyance, a means having a conveying claw ispreferable.

Additionally, the injection positioning mechanism, the conveying clawand the like of the robot hand for moving the green meat during theinjection process are preferably operated according to a preset programor a program based on the configuration or the like of the green meat.

A needleless pickle injector for use in the injection method of theinvention will be described with reference to FIGS. 6 and 7.

The needleless pickle injector is constituted of a liquid tank 1containing the liquid substance therein; a diaphragm pump 2; ahigh-pressure liquid generator 5 comprising a servo motor 3 and ahigh-pressure plunger pump 4 for operating the high-pressure plungerpump 4 with the servo motor 3 to increase a pressure of the liquidsubstance from the liquid tank 1; a high-pressure piping 6 constitutedof a flexible hose with a withstanding pressure of 3500 kg/cm² and astainless piping with a withstanding pressure of 4200 kg/cm² ; a robothand 14 with a tip end having a manifold 7 provided with a straightwater flow injection nozzle (coherent stream injection nozzle), acylinder piston 9 for vertically moving a green meat conveying claw 8,and a meat-thickness measurement section 12 constituted of apotentiometer 10, a spring 11 and the like, and with the above-mentionedtip end being controlled by a controller 13 or the like to be movablealong X, Y and Z axes (freely movable vertically, horizontally and backto forth); a green meat conveying section 15 connected to a green meatconveyor (not shown); and a green meat fixing guide 16 mounted on thegreen meat conveying section 15 in the injection position of the liquidsubstance.

The injection method using the device will be described. When a greenmeat 17 conveyed from the green meat conveyor is laid on one end of thegreen meat conveying section 15, the tip end of the robot hand 14 movestoward the green meat 17. The green meat conveying claw 8 attached tothe tip end is lowered by the cylinder piston 9 to catch the green meat17 and convey it to the injection position of the liquid substance. Thegreen meat 17 conveyed to the injection position is fixed by the greenmeat fixing guide 16. Additionally, the tip end of the robot hand 14 islowered, and the tip end of the manifold 7 presses against the greenmeat 17. Simultaneously, compression pressure is absorbed by the spring11. Its displacement is detected by the potentiometer 10 and calculated.Then, the meat thickness is automatically measured. Based on themeasured value calculated is a pre-programmed maximum injectionpressure. Information regarding the maximum injection pressure,pre-programmed injection reaching time and information regardinginjection ratio are transmitted to the servo motor 3. The servo motor 3operates the high-pressure plunger pump 4. The liquid substance isinjected as a coherent stream from the tip end of the injection nozzleof the manifold 7 in contact with the green meat. As a result, while theliquid substance is injected, the injection pressure is controlled.Specifically, the injection pressure is gradually raised from 0 or a lowpressure to the maximum injection pressure calculated in accordance withthe meat thickness for the injection time calculated based on theinjection ratio and at the pressure rising rate calculated from adifference in pressure up to the maximum injection pressure, while theliquid substance is injected to the green meat 17. Subsequently, theinjection pressure is returned to 0. If necessary, the next injection isperformed by moving the robot hand 14. The liquid substance is thusinjected to the entire green meat 17. The green meat 17 to which theliquid substance has been injected is conveyed by the green meatconveying claw 8 attached to the tip end of the robot hand 14.Thereafter, the aforementioned operation is repeated.

Since the green meat fixing guide 16 for fixing the green meat isprovided, no unnecessary scratches is made on the green meat. Also, whenthe manifold 7 provided with the injection nozzle is brought in contactwith the green meat 17, the thickness of the green meat is madeconstant. As a result, the pressure of the high-pressure liquidsubstance can be easily controlled. Additionally, to handle theexpansion of the green meat 17 by injection of the liquid substance, aspring or the like may be disposed around a mechanism for fixing thegreen meat 17.

Another embodiment of the needleless pickle injector for use in theinjection method of the invention will be described with reference toFIG. 8. Additionally, the same constituent portions as those of theaforementioned needleless pickle injector are denoted by the samenumerals.

The needleless pickle injector is constituted of a liquid tank 1containing the liquid substance therein; a high-pressure liquidgenerator 5 operated by a servo motor 3 to increase a pressure of theliquid substance from the liquid tank 1; a high-pressure piping 6constituted of a flexible hose with a withstanding pressure of 3500kg/cm² and a stainless piping with a withstanding pressure of 4200kg/cm² ; a flow-rate adjustment section 18; an X-axis drive jig 19 towhich a manifold 7 attached with a coherent stream injection nozzle isfixed; a Y-axis drive jig 20; a Z-axis drive jig 21; a controller 13 forcontrolling movements of the X-axis drive jig 19, the Y-axis drive jig20 and the Z-axis drive jig 21, positioning an injecting section andcontrolling an injection pressure; a green meat conveyor 22intermittently moving to convey a green meat 17 toward the injectingsection; and a green meat fixing guide 16 for pressing and fixing thegreen meat 17 from opposite sides at the time of injection.

The injection method using the device will be described. When the greenmeat moves at the time of injection, the green meat 17 conveyed by thegreen meat conveyor 22 is cut by a moved distance. For the prevention ofthis, the green meat is held and fixed by the green meat fixing guide16. The manifold 7 is then lowered from above to hit against the greenmeat. The controller 13 calculates the pressure rising rate inaccordance with the injection ratio and the maximum injection pressurein accordance with the height of the injecting section. Based oninformation regarding the maximum injection pressure, pre-programmedinjection reaching time and information regarding the injection ratio,the servo motor 3 operates the high-pressure plunger pump 4. The liquidsubstance is injected as a coherent stream from the tip end of theinjection nozzle attached to the manifold 7 in contact with the greenmeat. As a result, while the liquid substance is injected, the injectionpressure is controlled. After the injection at one position iscompleted, the controller 13 moves the manifold 7 to the next positionto perform the next inject on. After completing the injection to thegreen meat in the region of the length of the green meat fixing guide16, the green meat conveyor 22 is operated to convey the green meat. Byrepeating the aforementioned operation, the liquid substance isuniformly injected and dispersed into the green meat.

The injecting section of the injector can move in X, Y and Z directions.While the green meat 17 or another object of injection is fixed, bymoving the manifold 7, injection can be performed. When the injectingsection, i.e., the manifold 7 moves along three axes in the X, Y and Zdirections, by fixing one axis or two axes, only the movement alone twoaxes or one axis is feasible.

A structure of the manifold 7 as a main part of the pickle injector willbe described.

A member for branching a single flow from the high-pressure piping 6into plural flows is called the manifold 7. The conventional injectingsection of a high-pressure water device is of a single-hole system orhas a radially branched piping in the manifold. The inventors et al.have prepared the manifold 7 in such a manner that it can be used as thepickle injector for meat. A piping in a manifold is branched, andbranched pipes are arranged parallel. Here, the parallel arrangementincludes not only the arrangement where the pipes are arranged parallelin a row but also the arrangement where the pipes are arranged zigzag orparallel in multiple rows.

The high-pressure liquid substance is spouted as a coherent stream fromnozzles on tip ends of the pipes, and injection is simultaneouslyperformed from the arranged nozzles to the meat. Also, byinterconnecting plural manifolds or attaching multiple nozzles to onemanifold, the liquid substance can be efficiently injected in oneprocess.

A structure of the injecting section according to the invention will bedescribed with reference to FIGS. 9 and 10.

In the manifold 7, thirteen branch pipes 23 are arranged at an intervalof 10 mm and parallel in four rows at an interval of 10 mm. A coherentstream injection nozzle 24 is attached to a tip end of an injection holeof each branch pipe 23. An interval of adjoining nozzles 24corresponding to a needle interval in the conventional multi-needlepickle injector is set to 10 mm. Therefore, one manifold 7 can beprovided with a large number of branch pipes 23. A highly-denseinjection can be performed. Additionally, the hole diameter of thecoherent stream injection nozzle 24 is set to 3/1000 inch. It is knownthat the injection pressure is inversely proportional to the nozzle-holediameter multiplied four times. The smaller the diameter is, the higherpressure can be obtained.

The liquid substance is injected by the pickle injector constituted asaforementioned. In this case, since the means is provided forcontrolling the pressure while injecting, the pressure can be graduallyraised to the maximum injection pressure suitable for the meat thicknessat the pressure rising rate set in accordance with the injection ratio.When the pressure rises, the liquid substance in the green meat advancesfurther and is then dispersed transversely by the resistance of the nextmeat tissue. By repeating the operation, the liquid substance can beuniformly dispersed in the green meat.

Then, since no injection needle is used, the nozzle interval can beremarkably narrowed, as compared with the conventional multi-needlepickle injector. Additionally, in the constitution of the injectingsection, one or plural manifolds in which the branch pipes areparallelly arranged are connected, thereby accomplishing the pluralparallel injections by one drive at a high density. Therefore, in oneprocess, the liquid substance can be efficiently injected into the greenmeat and simultaneously dispersed.

Also, the method in which the injection depth can be controlled byadjusting the maximum injection pressure has been obtained. Therefore,the liquid substance can be uniformly injected and dispersed into thinand thick green meats by using the same machine. Also, the method inwhich the injection depth is controlled by adjusting the maximuminjection pressure and the method in which the injection quantity iscontrolled by adjusting the injection time have been obtained.Therefore, by adjusting the pressure rising rate, the injection ratiocan be controlled.

Further in the pickle injector for use in the invention, by using thehigh-pressure liquid generator, injection is performed under aremarkably higher pressure than the resistance pressure of the meat.Therefore, the liquid substance can be uniformly injected to both hardand soft meats in the same manner. It has been found that the differenceof injection resistance in meat property which is a problem of theconventional multi-needle pickle injector has little influence.

A method of manufacturing a raw ham by using the pickle injectorprovided with the injecting section of the invention will be described.In the injecting section, the coherent stream injection nozzles arearranged at a high density.

For the manufacture of the raw ham, a dry curing method, a brine curingmethod or a single needle injection method is used. However, in eithermethod, the manufacture requires much time. A dispersion tends to occurin a dispersed condition of curing agent in individual green meats, meatportions and surface and central portions. Since the raw ham has a highsalt concentration, the dispersion of the dispersed condition has alarge influence on a quality. Also, since no heating process isperformed; the curing agent needs to be dispersed with a sufficient carefor safety. Therefore, according to the food hygiene law, the injectionmethod by means of an automatic injector using multiple needles is notauthorized as the curing method of the raw ham. Because when the needlesare used, there is a possibility that the depth of the meat iscontaminated with microorganisms on the surface of the green meat. Also,the brine leaking from the meat at the time of injection is collectedfor reuse.

On the other hand, in the invention, since no needle is used, nocontamination of the microorganisms is caused by the needles inside thegreen meat. Simultaneously with injection, the brine is denselydispersed in the meat. At the time of injection the brine scarcely leaksfrom the meat. Therefore, the manufacture can be performed without usingthe brine contaminated with the microorganisms at the time of injection.

Additionally, since the brine is uniformly dispersed in the meat,simultaneously with injection all portions of the green meat, a securelylowered water activity value of cured meat is obtained as defined by thefood hygiene law. As aforementioned, according to the invention, theinjection liquid is uniformly dispersed in the meat. A fine dispersionoccurs, and a stabilized quality is obtained. Also in respect of safety,the number of bacteria and also the water activity value can conformwith specifications and standards of the food hygiene law.

Further, since the injection quantity of the Brine can be properlychanged, even a product with any salt concentration can be easilyprepared.

Next, embodiments of the invention will be described in more detail, butthe technical scope of the invention is not limited to theseembodiments.

Embodiment 1

By using the aforementioned injection device, injection is performed asfollows. When the pork block 17 conveyed from the green meat conveyor islaid on one end of the green meat conveying section 15, the tip end ofthe robot hand 14 moves toward the pork block 17. By the green meatconveying claw 8 attached to the tip end, the pork block 17 is conveyedto the injection position of the liquid substance. The pork block 17conveyed to the injection position is fixed by the green meat fixingguide 16. Additionally, the tip end of the robot hand 14 is lowered, andthe tip end of the manifold 7 presses against the pork block 17.Simultaneously, compression pressure is absorbed by the spring 11. Itsdisplacement is detected by the potentiometer 10 and calculated. Then,the meat thickness is automatically measured. On the basis of themeasured value, a pre-programmed maximum injection pressure iscalculated. Information regarding the maximum injection pressure,pre-programmed injection reaching time and information regardinginjection ratio are transmitted to the servo motor 3. The servo motor 3operates the high-pressure plunger pump 4. The liquid substance isinjected as a coherent stream from the tip end of the injection nozzle24 in contact with the pork block. The pressure is returned to 0.Subsequently, the operation is repeated in accordance with the programof the robot hand 14 incorporated in the controller 13. After the liquidsubstance is injected to the entire pork block 17, the pork block 17 isconveyed outside by the green meat conveying claw 8 attached to the tipend of the robot hand 14.

FIG. 11 shows a comparison of a distributed condition of salt contentafter injection between the test and a test which was performed by usingthe same liquid substance, the equivalent pork block and theconventional multi-needle pickle injector. The upper half of FIG. 11shows the distributed condition of salt content after injection when thepickle injector of the invention is used. The lower half thereof showsthe distributed condition of salt content after injection when theconventional multi-needle pickle injector is used. Additionally, theleft side shows the distributed condition immediately after injection,while the right side shows the distributed condition after the porkblock is cured for 72 hours.

The distributed condition is measured by dividing each pork blockvertically into two and horizontally into three to obtain test pieces ofsix positions in total. As clearly seen from FIG. 11, in the injectionmethod into the meat according to the invention, the liquid substancecan be remarkably uniformly injected and simultaneously uniformlydispersed, as compared with the conventional multi-needle pickleinjector.

Embodiment 2

An embodiment of the pickle injector of the invention using an injectingsection with coherent stream injection nozzles arranged therein at ahigh density will be described.

Table 1 shows a comparison of injection ratio between the injection withthe pickle injector including the injecting section with 60 coherentstream injection nozzles attached thereto to portions of pork ham:outside; inside; rump; knuckle and outside (M. Semitendinosus), and theinjection with the conventional multi-needle pickle injector.Additionally, 40 blocks were used as sample pork blocks for eachinjection case.

[Table 1]

As seen from Table 1, for the standard deviation in the whole, theconventional multi-needle pickle injector shows 7.3%. On the other hand,in the injection method of the invention the deviation is very small as0.8%. A remarkably fine dispersion of the injection ratio occurs.

Additionally, in the conventional multi-needle pickle injector, maximumand minimum values are treated as defective numerical values. In theinvention, however, maximum and minimum values are in an allowableproduct range. It has been found that by using the pickle injector ofthe invention, the number of defective products is reduced.

Embodiment 3

Another embodiment of the pickle injector of the invention using theinjecting section with coherent stream injection nozzles arrangedtherein at a high density will be described.

Table 2 shows a comparison of the injection ratio of injection to porkloin between the pickle injector of the invention and the conventionalmulti-needle pickle injector. As samples, 50 blocks of pork blocks wereused.

[Table 2]

Pork loin is a long green meat called M. Longissimus dorsi extendingfrom shoulders to ham. The meat on the side of ham is harder. When theliquid substance is injected to one block of loin in the same manner,usually the liquid substance does not easily enter the meat on the sideof thighs and excessively enters the meat on the side of shoulders.

A right column of Table 2 shows results of the conventional multi-needlepickle injector. Toward the meat on the side of shoulders the injectionratio increases. Additionally, a large dispersion occurs.

A left column of Table 2 shows results of the pickle injector of theinvention. The hardness of the meat has little influence, and a smalldispersion occurs.

Embodiment 4

An embodiment of injection to fish meat with the pickle injector of theinvention using the injecting section with coherent stream injectionnozzles arranged therein at a high density will be described. A halfpiece of salmon was divided into four from head toward tail. Table 3shows a comparison of the injection ratio between the pickle injector ofthe invention and the conventional injector (the number of samples isten for each). Additionally, as samples, 10 salmons were used.

[Table 3]

In the fish meat there is a gradient in thickness from head toward tail.The liquid substance does not easily enter a thin tail meat.

As shown in Table 3, when the conventional injector is used, theinjection ratio in the thin tail meat is lower than in a thick middlemeat. However, when the pickle injector of the invention is used, thethickness has little influence on the injection ratio.

Also, for the standard deviation of the whole, as compared with 5.5% ofthe conventional injector, 0.8% of the pickle injector of the inventionis very small. It has been clarified that in the same manner as theaforementioned embodiments of pork loin and ham, even in the injectionto the fish meat, the dispersion of the injection ratio is remarkablyreduced.

Embodiment 5

An embodiment of injection of a brine with red No. 3 for food coloringdissolved therein to pork loin with the pickle injector of the inventionwill be described. The pickle injector is provided with the injectingsection in which coherent stream injection nozzles are arranged at ahigh density.

FIG. 12 shows a comparison of a dispersed condition in the case ofinjection of the injection liquid to pork loin between the pickleinjector of the invention and the conventional multi-needle pickleinjector. The upper half of FIG. 12 shows the dispersed condition afterthe injection using the pickle injector of the invention. The lower halfshows the dispersed condition after the injection using the conventionalmulti-needle pickle injector. Also, the left side shows the dispersedcondition immediately after the injection, while the right side showsthe dispersed condition after the pork loin is cured for 72 hours.

As clarified by results shown in FIG. 12, when the conventionalmulti-needle pickle injector is used for injection, a poorly dispersedcondition is obtained immediately after the injection. The red No. 3 forfood coloring or another substance which has a high reactivity withprotein in the meat cannot move after injected into the green meat.Therefore, no change occurs in the dispersed condition even after thegreen meat is cured for 72 hours. On the other hand, when the pickleinjector of the invention is used for injection, the red No. 3 for foodcoloring is uniformly dispersed immediately after the injection.

Embodiment 6

Table 4 shows the yield during manufacturing processes, the manufactureperiod and the results of sensory evaluation on products in the case ofmanufacture by using the injection method of the invention and theconventional dry curing method.

As seen from Table 4, in the dry curing method, curing time requires 2weeks and completing products requires about three weeks. On the otherhand, in the injection method of the invention, curing requires 1 dayand completing products requires less than one week. The manufactureperiod can be largely reduced. Additionally, the manufacture yield isincreased. Also, in the sensory evaluation, there is no dispersion ofsalt content, and there is a wet and satisfactory feel. The sensoryevaluation was performed by a ten-specialist panel.

As aforementioned, according to the injection method of the invention,the brine is uniformly dispersed in the meat, and a stable quality witha fine dispersion is obtained. For safety, the number of bacteria andalso the water activity value conform with specifications and standardsof the food hygiene law. Such raw-ham product can be obtained.

[Table 4]

Embodiment 7

In the curing process for the manufacture of a raw ham by using a blockof pork loin, transition results of manufacture periods and wateractivity values of central portions are shown in FIG. 13 for the casesof manufacture in which the injection method of the invention, theconventional single needle injection method and the brine curing methodare applied. As seen from FIG. 13, according to the method of theinvention, the injection liquid is uniformly dispersed in the meat witha fine dispersion. In only one day for curing, the water activity valuebecomes less than 0.97. The curing period can be largely reduced, ascompared with the single-needle method and the brine curing method.Also, in the same manner as the raw-ham product manufactured in theaforementioned conventional method, the number of bacteria in theraw-ham product manufactured according to the invention conforms withthe specifications and standards of the food hygiene law. In therequirement, in 1 g of test specimen, the number of Escherichia coli(E.coli) is 100 or less, the number of staphylococcus aureus is 1000 orless and salmonella exhibits negative. According to the invention, araw-ham product with no problem also in respect of safety can beobtained.

Industrial Applicability

As clearly seen from the above description, the present invention hasthe following effects:

1. By the method in which the high-pressure pickle injector is used, themeat and the coherent stream injection nozzle are brought in contactwith each other and the pressure is controlled while injecting theliquid substance, the liquid substance can be remarkably uniformlyinjected and dispersed as compared with the conventional method. Themethod of the invention can be applied to the method of manufacturingraw ham.

Further, in the method, the ununiformity of injection of the liquidsubstance caused by the difference of injection resistance in meatproperty can also be solved.

2. Further, the method can be used to physically disperse a substancewith a bad dispersed property in green meat. The substance which has notbeen able to be used in the brine composition for curing can be used.

3. Since the uniform dispersion is substantially completed immediatelyafter the injection, a dynamic stimulus does not need to be applied fora long time with a tumbling machine, a massage machine or the like. Thecuring time or the seasoning time can be largely reduced.

4. The method of controlling the injection depth by adjusting themaximum injection pressure is obtained. Therefore, the liquid substancecan be uniformly injected and dispersed into thin and thick green meats.Also, since no needle is used, the liquid substance can be uniformlyinjected and dispersed into fish meat or raw-material meat with bones orskins to which the multi-needle type cannot be applied or is defectivelyapplied.

5. The method of controlling the injection depth can be obtained byadjusting the maximum injection pressure, and the method of controllingthe injection quantity can be obtained by adjusting the injection time.Therefore, by adjusting the pressure rising rate, the injection ratiocan be controlled. Products with different injection ratios and multiplestandards can be manufactured.

                  TABLE 1                                                         ______________________________________                                                      PICKLE    CONVENTIONAL                                                        INJECTOR  MULTI-NEEDLE                                                        OF THE    PICKLE                                                              APPLICATION                                                                             INJECTOR                                              ______________________________________                                        OUTSIDE  AVERAGE    121.2       108.8                                                  VALUE                                                                         STANDARD   0.8         1.0                                                    DEVIATION                                                                     MAXIMUM    122.5       109.7                                                  VALUE                                                                         MINIMUM    120.0       107.0                                                  VALUE                                                                INSIDE   AVERAGE    121.1       127.1                                                  VALUE                                                                         STANDARD   0.8         4.8                                                    DEVIATION                                                                     MAXIMUM    122.2       134.7                                                  VALUE                                                                         MINIMUM    120.0       121.1                                                  VALUE                                                                RUMP     AVERAGE    121.5       125.1                                                  VALUE                                                                         STANDARD   0.8         3.8                                                    DEVIATION                                                                     MAXIMUM    122.3       132.8                                                  VALUE                                                                         MINIMUM    120.0       120.4                                                  VALUE                                                                KNUCKLE  AVERAGE    121.2       120.7                                                  VALUE                                                                         STANDARD   0.8         3.2                                                    DEVIATION                                                                     MAXIMUM    122.0       130.6                                                  VALUE                                                                         MINIMUM    120.0       113.3                                                  VALUE                                                                OUTSIDE  AVERAGE    120.3       122.4                                         (H.Semitendino                                                                         VALUE                                                                sus)     STANDARD   0.7         3.9                                                    DEVIATION                                                                     MAXIMUM    121.1       126.3                                                  VALUE                                                                         MINIMUM    119.2       115.9                                                  VALUE                                                                WHOLE    AVERAGE    121.1       120.8                                                  VALUE                                                                         STANDARD   0.8         7.3                                                    DEVIATION                                                                     MAXIMUM    122.5       134.7                                                  VALUE                                                                         MINIMUM    119.2       107.0                                                  VALUE                                                                ______________________________________                                    

                  TABLE 2                                                         ______________________________________                                         ##STR1##                                                                                                     CONVENTIONAL                                                    PICKLE INJECTOR                                                                             MULTI-NEEDLE                                                    OF THE        PICKLE                                                          APPLICATION   INJECTOR                                      ______________________________________                                        (1)    AVERAGE    120.2         113.9                                                VALUE                                                                         STANDARD   0.8           3.4                                                  DEVIATION                                                                     MAXIMUM    121.3         120.3                                                VALUE                                                                         MINIMUM    118.8         108.6                                                VALUE                                                                  (2)    AVERAGE    120.3         119.3                                                VALUE                                                                         STANDARD   0.7           5.2                                                  DEVIATION                                                                     MAXIMUM    121.1         125.3                                                VALUE                                                                         MINIMUM    118.9         110.6                                                VALUE                                                                  (3)    AVERAGE    120.7         122.8                                                VALUE                                                                         STANDARD   0.7           4.3                                                  DEVIATION                                                                     MAXIMUM    121.6         128.3                                                VALUE                                                                         MINIMUM    119.8         115.3                                                VALUE                                                                  (4)    AVERAGE    120.5         124.6                                                VALUE                                                                         STANDARD   0.7           5.3                                                  DEVIATION                                                                     MAXIMUM    121.8         130.5                                                VALUE                                                                         MINIMUM    119.4         115.6                                                VALUE                                                                  WHOLE  AVERAGE    120.4         120.2                                                VALUE                                                                         STANDARD   0.7           6.1                                                  DEVIATION                                                                     MAXIMUM    121.8         130.5                                                VALUE                                                                         MINIMUM    118.8         108.6                                                VALUE                                                                  ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                         ##STR2##                                                                                       PICKLE INJECTOR                                                               OF THE        CONVENTIONAL                                                    APPLICATION   INJECTOR                                      ______________________________________                                        (1)    AVERAGE    110.3         109.8                                                VALUE                                                                         STANDARD   0.9           4.8                                                  DEVIATION                                                                     MAXIMUM    111.6         118.4                                                VALUE                                                                         MINIMUM    109.2         104.1                                                VALUE                                                                  (2)    AVERAGE    110.1         113.7                                                VALUE                                                                         STANDARD   0.6           5.1                                                  DEVIATION                                                                     MAXIMUM    110.9         121.3                                                VALUE                                                                         MINIMUM    109.2         106.9                                                VALUE                                                                  (3)    AVERAGE    109.7         112.8                                                VALUE                                                                         STANDARD   0.6           5.7                                                  DEVIATION                                                                     MAXIMUM    110.5         122.6                                                VALUE                                                                         MINIMUM    108.9         105.8                                                VALUE                                                                  (4)    AVERAGE    109.8         106.2                                                VALUE                                                                         STANDARD   0.9           3.5                                                  DEVIATION                                                                     MAXIMUM    110.8         113.4                                                VALUE                                                                         MINIMUM    108.5         102.4                                                VALUE                                                                  WHOLE  AVERAGE    110.0         110.6                                                VALUE                                                                         STANDARD   0.8           5.5                                                  DEVIATION                                                                     MAXIMUM    111.6         122.6                                                VALUE                                                                         MINIMUM    108.5         102.4                                                VALUE                                                                  ______________________________________                                    

                                      TABLE 4                                     __________________________________________________________________________                 MANUFACTURE METHOD OF                                                         THE INVENTION  DRY CURE METHOD                                                PROCESS                                                                             MANUFACTURE                                                                            PROCESS                                                                            MANUFACTURE                                               YIELD PERIOD   YIELD                                                                              PERIOD                                       __________________________________________________________________________    BLENDING                                                                              MEAT 100.0%         100.0%                                                    CURING                                                                             10.0%          10.0%                                                     AGENT                                                                              110.0%         110.0%                                                    TOTAL                                                                 CURING YIELD 99.4% 1 DAY    90.0%                                                                              14 DAYS                                      DRYING YIELD 84.9% 5 DAYS   85.0%                                                                               5 DAYS                                      TOTAL        92.8% 6 DAYS   84.2%                                                                              19 DAYS                                      SENSORY FEEL SOFT AND GOOD  DRY AND HARD                                      EVALUATION                                                                            TASTE                                                                              GOOD           PARTIALLY SALTY                                   __________________________________________________________________________

What is claimed is:
 1. A method for injecting a liquid substance into agreen meat wherein, when the liquid substance is injected into the greenmeat by using a straight water flow injection nozzle or a coherentstream injection nozzle, the injection pressure is controlled while theliquid substance is being injected.
 2. The method of injecting a liquidsubstance into the green meat according to claim 1 wherein the change ofthe injection pressure is performed by a gradual rise of the injectionpressure from 0 or a low pressure.
 3. The method of injecting a liquidsubstance into the green meat according to either of claim 1 wherein bycontrolling a maximum value of the injection pressure, an injectiondepth of the liquid substance is controlled.
 4. The method of injectinga liquid substance into the green meat according to claim 3 wherein themaximum value of the injection pressure is 7 to 3000 kg/cm².
 5. Themethod of injecting a liquid substance into the green meat according toeither of claim 1 wherein by controlling an injection time elapsed untilthe maximum value of the injection pressure is reached, an injectionquantity of the liquid substance is controlled.
 6. The method ofinjecting a liquid substance into the green meat according to claim 5wherein the injection time taken until the maximum value of theinjection pressure is reached is in the range of 0.05 to 10 seconds. 7.The method of injecting a liquid substance into the green meat accordingto either of claim 1 wherein by changing a rising rate of the injectionpressure, an injection ratio of the liquid substance into the green meatis controlled.
 8. The method of injecting a liquid substance into thegreen meat according to claim 7 wherein the rising rate of the injectionpressure is 100 to 20000 kg/cm² ·second.
 9. The method of injecting aliquid substance into the green meat according to either of claim 1wherein the maximum value of the injection pressure is regulated to apredetermined value in accordance with physical properties of the greenmeat.
 10. The method of injecting a liquid substance into the green meataccording to either of claim 1 wherein processes of measuring a meatthickness of the green meat, calculating the maximum value of theinjection pressure based on a measured value and performing a pressurecontrol are all automated.
 11. The method of injecting a liquidsubstance into the green meat according to either of claim 1 wherein themaximum value of the injection pressure is regulated to a predeterminedvalue in accordance with the meat thickness of the green meat.
 12. Themethod of injecting a liquid substance into the green meat according toeither of claim 1 wherein a pressure rising rate is regulated to apredetermined value in accordance with physical properties of the liquidsubstance.
 13. The method of injecting a liquid substance into the greenmeat according to either of claims 1 wherein the green meat is fixed.14. The method of injecting a liquid substance into the green meataccording to either of claim 1 wherein the coherent stream injectionnozzle is brought in contact with the green meat.
 15. The method ofinjecting a liquid substance into the green meat according to either ofclaim 1 wherein the coherent stream injection nozzle which can performinjection from one direction or two or more directions in accordancewith a configuration of the green meat is used.
 16. The method ofinjecting a liquid substance into the green meat according to either ofclaim 1 wherein by narrowing an injection interval, the injection isperformed.
 17. A method for manufacturing a meat product comprisinginjecting a liquid substance into a green meat according to the methodof claim
 1. 18. The method according to claim 17 wherein the meatproduct is an uncooked meat product.
 19. The method according to claim18, wherein the uncooked meat product is a raw ham.
 20. A liquidsubstance injected meat product prepared according to the process ofclaim
 1. 21. The meat product according to claim 20, wherein the meatproduct is an uncooked meat product.
 22. The meat product according toclaim 21, wherein the uncooked meat product is a raw ham.